45-70 BC with 300 to 400 gr bullets

[NFG]

Anyone tried any of the premium bullets such as Swift, Nosler, Barnes, etc?

 I'm particularly interested in 300 to 350 gr and would like some data before I empty my wallet for a few boxes.  I have worked up some loads in my H&R BC using Speer and Hornady bullets that seem very nice with velocities at 2698 f/s using 60 gr IMR 4198 with Hornady 300's and 2256 f/s using 51 gr IMR 4198 with Speer 400's.  Both are compressed, within 2 gr or so of the listed maximuns but are as far as I want to go due to the compression of the powder.

Tim recommended that velocity was way over what Sierra and Speer 300 gr bullets could stand for Elk and above due to the bullet not holding together well.  I haven't taken any game with the 45-70 yet so I can't comment on these bullets, but I do know that the all copper or Partition bullets would work.  I just haven't come across much data other than the Nosler PT in reguards to Barnes X or Swift bullets and actual whacking the big beasties but I'm starting to look and would appreciate any links to real world stuff.

Thanks  NFG

And any pressure data using those hard bullets.

I particularly like Barnes 350 X and Swift 350 gr.  Both have high BC's so would put the 45-70 into the 300 yd realm realistically, plus penetrate from one end to the other, if a Texas Heart shot should present itself.

I will post whatever I come up with as long as everyone uses the caveat of "this data is for use in NFG's BC only".

[quickdtoo]

Tim recommended that velocity was way over what Sierra and Speer 300 gr bullets could stand for Elk and above due to the bullet not holding together well.

Dunno about the Speer and Sierra bullets, my recommendation was not to use the Hornady bullet which was your first test platform.

I've been working on a 300 gr load for my BC for the past couple of days and came up with a good one.

Using Hornady's #4500, 300 gr HP, 57 gr IMR 4198, WLR and R-P brass I got 2598 f/s. 58 gr gave me 2618 f/s. Looks like 57 is about it. Brass expansion was linear starting at 51 gr and going up one grain at a time, about 0.0002" per grain. I extrapolated, interpolated and cogitated and guessed the pressure to be 40800 with the 58 gr load, well within safety parameters. I have some Speer and Nosler 300's to try also.

http://www.marlinowners.com/board/viewtopic.php?t=14070

Here's Speer's data...

http://home.comcast.net/~quickdtoo/4570_300.pdf

Tim

And some more interesting info...

http://www.marlinowners.com/board/viewtopic.php?t=11969&highlight=4570+data

[NFG]

WHOOPS, Sorry about the miss quote, TIM.  I ment Hornady and Speer and wrote Sierra and Speer.  Too many things going on mentally at the same time and Murphy stepped in.  See how easy things can get out of hand on the net.  

I ran my data through "Load with a disk" and the pressures came out slightly over 51,000 psi.  Dropping one or two grains would be better, for what it's worth.  Velocities were within 50 f/s also so I feel better now I have something to compare and know the pressures are within reason.

Using the longer solid copper bullets changed things quite a bit, so a guy needs to creep up slowly with those pointy things.  Those Barnes 300 XFB's with their high BC's sure look nice.  Need to try them for sure.

Enjoy  NFG

[quickdtoo]

Not a problem, stuff happens!!

I'm working with the .411" 350gr Barnes XFB in my .405 Winchester Target, it's got an SD of .296 and BC of 536, so it should be a good long range killer if I can ever get to the range to shoot the loads I have worked up. Ty Herrings at Barnes suggested I use the Hodgdon data for the 400gr Woodleigh solid, so that's what I'm doing with my H4895 for the time being.

Tim

[sphingta]

The 300 grain loads with 60 grains of 4198 seem pretty stout. just out of curiousity what does load from a disk say. I'll post what quick load says and you can tell me if they're are any differences. By the way I put in 35,000 psi as max pressure rating.


Cartridge          : .45-70 Govt. SAAMI
Bullet             : .458, 300, SPR FN 2482
Cartridge O.A.L. L6: 2.550 inch or 64.77 mm
Barrel Length      : 32.0 inch or 812.8 mm
Powder             : IMR 4198

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-20.0   89    48.00   2249    3369   33431   2523     97.5    1.684
-18.0   91    49.20   2295    3509   35628   2572     98.1    1.644  ! Near Maximum !
-16.0   94    50.40   2341    3650   37967   2617     98.6    1.605  ! Near Maximum !
-14.0   96    51.60   2386    3792   40458   2658     99.0    1.564  !DANGEROUS LOAD-DO NOT USE!
-12.0   98    52.80   2431    3936   43115   2694     99.4    1.525  !DANGEROUS LOAD-DO NOT USE!
-10.0  100    54.00   2475    4080   45948   2726     99.7    1.488  !DANGEROUS LOAD-DO NOT USE!
-08.0  103    55.20   2518    4225   48974   2754     99.9    1.452  !DANGEROUS LOAD-DO NOT USE!
-06.0  105    56.40   2562    4371   52205   2777    100.0    1.418  !DANGEROUS LOAD-DO NOT USE!
-04.0  107    57.60   2604    4517   55665   2795    100.0    1.385  !DANGEROUS LOAD-DO NOT USE!
-02.0  109    58.80   2646    4664   59368   2810    100.0    1.353  !DANGEROUS LOAD-DO NOT USE!
+00.0  112    60.00   2688    4811   63337   2825    100.0    1.322  !DANGEROUS LOAD-DO NOT USE!
+02.0  114    61.20   2729    4959   67597   2839    100.0    1.292  !DANGEROUS LOAD-DO NOT USE!
+04.0  116    62.40   2769    5108   72176   2852    100.0    1.264  !DANGEROUS LOAD-DO NOT USE!
+06.0  118    63.60   2809    5257   77102   2864    100.0    1.236  !DANGEROUS LOAD-DO NOT USE!
+08.0  120    64.80   2849    5407   82415   2875    100.0    1.210  !DANGEROUS LOAD-DO NOT USE!
+10.0  123    66.00   2889    5558   88079   2885    100.0    1.184  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    112    60.00   2754    5052   74599   2687    100.0    1.259  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    112    60.00   2582    4441   52872   2970     98.8    1.410  !DANGEROUS LOAD-DO NOT USE!